Multifluids for Representing Subgrid‐Scale Convection

Abstract Traditional parameterizations of convection are a large source of error in weather and climate prediction models, and the assumptions behind them become worse as resolution increases. Multifluid modeling is a promising new method of representing subgrid‐scale and near‐grid‐scale convection...

Descripción completa

Guardado en:

Detalles Bibliográficos
Autores principales:	Hilary Weller, William McIntyre, Daniel Shipley
Formato:	article
Lenguaje:	EN
Publicado:	American Geophysical Union (AGU) 2020
Materias:	convection parameterization numerical modeling multifluid net mass transport Physical geography GB3-5030 Oceanography GC1-1581
Acceso en línea:	https://doaj.org/article/d523e9d40ff34c94921fb65edbc87934
Etiquetas:	Agregar Etiqueta Sin Etiquetas, Sea el primero en etiquetar este registro!

id	oai:doaj.org-article:d523e9d40ff34c94921fb65edbc87934
record_format	dspace
spelling	oai:doaj.org-article:d523e9d40ff34c94921fb65edbc879342021-11-15T14:20:27ZMultifluids for Representing Subgrid‐Scale Convection1942-246610.1029/2019MS001966https://doaj.org/article/d523e9d40ff34c94921fb65edbc879342020-08-01T00:00:00Zhttps://doi.org/10.1029/2019MS001966https://doaj.org/toc/1942-2466Abstract Traditional parameterizations of convection are a large source of error in weather and climate prediction models, and the assumptions behind them become worse as resolution increases. Multifluid modeling is a promising new method of representing subgrid‐scale and near‐grid‐scale convection allowing for net mass transport by convection and nonequilibrium dynamics. The air is partitioned into two or more fluids, which may represent, for example, updrafts and the nonupdraft environment. Each fluid has its own velocity, temperature, and constituents with separate equations of motion. This paper presents two‐fluid Boussinesq equations for representing subgrid‐scale dry convection with sinking and w = 0 air in Fluid 0 and rising air in Fluid 1. Two vertical slice test cases are developed to tune parameters and to evaluate the two‐fluid equations: a buoyant rising bubble and radiative convective equilibrium. These are first simulated at high resolution with a single‐fluid model and conditionally averaged based on the sign of the vertical velocity. The test cases are next simulated with the two‐fluid model in one column. A model for entrainment and detrainment based on divergence leads to excellent representation of the convective area fraction. Previous multifluid modeling of convection has used the same pressure for both fluids. This is shown to be a bad approximation, and a model for the pressure difference between the fluids based on divergence is presented.Hilary WellerWilliam McIntyreDaniel ShipleyAmerican Geophysical Union (AGU)articleconvectionparameterizationnumerical modelingmultifluidnet mass transportPhysical geographyGB3-5030OceanographyGC1-1581ENJournal of Advances in Modeling Earth Systems, Vol 12, Iss 8, Pp n/a-n/a (2020)
institution	DOAJ
collection	DOAJ
language	EN
topic	convection parameterization numerical modeling multifluid net mass transport Physical geography GB3-5030 Oceanography GC1-1581
spellingShingle	convection parameterization numerical modeling multifluid net mass transport Physical geography GB3-5030 Oceanography GC1-1581 Hilary Weller William McIntyre Daniel Shipley Multifluids for Representing Subgrid‐Scale Convection
description	Abstract Traditional parameterizations of convection are a large source of error in weather and climate prediction models, and the assumptions behind them become worse as resolution increases. Multifluid modeling is a promising new method of representing subgrid‐scale and near‐grid‐scale convection allowing for net mass transport by convection and nonequilibrium dynamics. The air is partitioned into two or more fluids, which may represent, for example, updrafts and the nonupdraft environment. Each fluid has its own velocity, temperature, and constituents with separate equations of motion. This paper presents two‐fluid Boussinesq equations for representing subgrid‐scale dry convection with sinking and w = 0 air in Fluid 0 and rising air in Fluid 1. Two vertical slice test cases are developed to tune parameters and to evaluate the two‐fluid equations: a buoyant rising bubble and radiative convective equilibrium. These are first simulated at high resolution with a single‐fluid model and conditionally averaged based on the sign of the vertical velocity. The test cases are next simulated with the two‐fluid model in one column. A model for entrainment and detrainment based on divergence leads to excellent representation of the convective area fraction. Previous multifluid modeling of convection has used the same pressure for both fluids. This is shown to be a bad approximation, and a model for the pressure difference between the fluids based on divergence is presented.
format	article
author	Hilary Weller William McIntyre Daniel Shipley
author_facet	Hilary Weller William McIntyre Daniel Shipley
author_sort	Hilary Weller
title	Multifluids for Representing Subgrid‐Scale Convection
title_short	Multifluids for Representing Subgrid‐Scale Convection
title_full	Multifluids for Representing Subgrid‐Scale Convection
title_fullStr	Multifluids for Representing Subgrid‐Scale Convection
title_full_unstemmed	Multifluids for Representing Subgrid‐Scale Convection
title_sort	multifluids for representing subgrid‐scale convection
publisher	American Geophysical Union (AGU)
publishDate	2020
url	https://doaj.org/article/d523e9d40ff34c94921fb65edbc87934
work_keys_str_mv	AT hilaryweller multifluidsforrepresentingsubgridscaleconvection AT williammcintyre multifluidsforrepresentingsubgridscaleconvection AT danielshipley multifluidsforrepresentingsubgridscaleconvection
_version_	1718428404106133504

Multifluids for Representing Subgrid‐Scale Convection

Ejemplares similares